Electric



March 4, 1952 A. B. PooLE ELECTRIC ALARM CLOCK Filed Igov. 1o, 1949 Patented Mar. 4, 1952 UNITED STATES PATENT OFFICE ELECTRIC ALARM CLOCK Arthur B.. Poole, llarwinton,v C onn. Application November 10, 1949, Serial Nin-126,487;

Claims. l

The present invention relatesA in general to electrically-operated alarm clocks and more, especially to improved alarm-mechanism and actuating-means therefor.

A n object of the invention is to providev an alarmv clock with superior alarm-mechanism characterized by compactness and simplicity of construction. as well as low cost of manufacture, dependability,v andV freedom from derangement.

AfurtloerV object of the invention is to provide an electric alarm clock with superior alarmmechanism wherein the alarm-armature of the alarm-mechanism is actuated by energization of the eld magnet of the electric motor.

A `still further object of the invention is to provide an electric alarm clock with alarm, mechanism having a superior alarm-armature adapted to be cooperatively associated with the eld magnet of the electric motor for vibration thereby, and movable to and from operative relationship with the field magnet in a direction substantially perpendicular to the direction of vibration of the alarm-armature.

A still further object of the invention is to provide the alarm-armature of the alarmmechanism of an electric alarm clock with superior mounting-means wherein the alarm-armature isl movable to and from operative relationship with the alarm-armature vibrating-means of the clock in a direction substantially perpendicular to the direction of vibration of the alarmarmature..

A still further object of the invention is to provide a superior electric alarm clock with alarm-.mechanism including alarm-setting means wherein tne alarm-set hand is,v mounted concentric with the time-indicating hands of the clock, to provide a clock of improved appearance.

Qther objects and advantages will appear to those skilled in the art from the following, considered conjunction with the accompanying drawingst.

Inthe accompanying drawings., in which oortain modes of carrying out the present invention are shown for illustrative purposes:

Fig. 1 is a Schematic elevation of the electric motor and time-train of an electric alarm clockl showing the alarm-mechanism in perspective; Fig. 2` is an enlarged side elevation partly in section of an, electric alarm clock with the outer casing removed but including the dial and the timo-indicating hands of the. time-train; and

Fia, 3 is a fragmentary plan View in. Section online 3er-.3 or Fig. 2 Showing details-of the alarmarmature. the auxiliary pole-pieces of the motor,

and the sounding-plate interposedl therebetween.

Although the present invention may be used with many diierent typesA of clocks operating' on an alternating-current supply,v it is shown as particularly adapted for use with a synchronous-motor-driven clock of the self-starting type.

ReferringV especially to Fig. l, the self-starting synchronous -motor-driven clock comprises,V in the main, a bipolar ield magnet or stator I! of oo nventional laminated construction, having oppositely-disposed poles [l and i2l provided with shading-coils |3 and, I4 respectively so as to cause the magnetism in one pole-.face to lagr somewhat behind the magnetism of the opposite pole-face and.. hence. produce., a Split-ollas@ r0- tating eld therebetweeny in which a rotor l5 is mounted. The magnetism inthe opposite poles il and l2 respectively of the iield magnet is created by a field-coil I6 mounted thereon and connected by suitable leads to a source of alterhating current. u

As shown especially Well in Fig, 2, the electric motor is mounted within a cup-shaped casing I'I,A the open end of which is sealed by an endclosure plate lll, the entire assembly Vbeing secured by bolts orA equivalent fastening-means on the rear face of the baci; movement-plate I9 of the clock.y In the preferred construction, the U-shaped casing Il and its end-closure plate I8 are formed of metal, the end-closure plate being a nonmagnetic metal. Although its primary function is that of sealing the open end of the motor-casing, the end-plate i8 is adapted also to be engaged by the alarm-armature hereinafter described, to sound the alarm, and hence is hereinafter referred to as a sounding-plate.

The aforesaid back movement-plate i9 of the clock is held in spaced substantially-parallel relationship to the front movement-plate 2i)A by means of the usual pillars, the front and back movement-plates and their pillars thereby forming a frame in which the time-train and associated elements of thel motor and alarm are assembled.

The time-train embodies a seconds-arbor 2l,V the drive for which is taken from the stair of the motor rotor I5 by way of the drive-pinion 22 and the train of gearing shown in Fig. 1 which train includes a seconds gear-Wheel 23 driven from the drive-pinion 22 by suitable reductiongearing, and provided with a pinion 2K4 which, through additional reductionfgearing, drives the minute gear-wheel 25. and its pinion 26, the minuio soar-Wheel 25. having an, elongated concentric bearing-sleeve 27, by which the minute gear- 3 wheel is rotatably mounted on the seconds-arbor 2|. The forward end of the elongated bearingsleeve 21, hereinafter referred to as the minutesleeve, projects through a central aperture 28 of the clock-dial 29, which is xedly secured in a conventional manner to the front face of the front movement-plate 29. Rotatably supported on the minute-sleeve 21 of the minute gear-wheel is the hour-sleeve 39 of an hour gear-wheel 3i which is driven from the minute gear-wheel pinion 26 through the dial-wheel 32 and its pinion 33, the hour-sleeve 39 being slidable longitudinally on the minute-sleeve 21 for releasing the alarm, as hereinafter described. As shown especially well in Fig. 2, the forward end of the hour-sleeve 39 projects through the central aperture 28 of the clock-dial 29 in concentric relation to the minute-sleeve 21.

ting gear by means of a leaf spring 36 which.

bears against the underside of the hour gearwheel 3 I. To this end, one end of the leaf spring 36 is riveted or similarly secured to the front face of the front movement-plate, the opposite end of the leaf spring 36 being free and provided at its extremity with a lip 31 bent at substantially right angles thereto, as shown especially well in Fig. 2, and arranged to project through an aperture 38 in the front movement-plate so as to engage the alarm-mechanism, as and for the purpose hereinafter described, the lip 31 being hereinafter referred to as the alarm-latch. The portion of the leaf spring 36 intermediate its opposite ends is enlarged transversely, as indicated at 39 in Fig. l, so as to provide maximum engagement with the underside of the hour gear-wheel 3l, the central enlargement 39 of theleaf spring being provided with an elongated clearance-aperture 49 for accommodating the minute-sleeve 21 of the minute gear-wheel.

j The aforesaid alarm-setting gear 35 is adapted to be rotatably supported on the back face of the fixed clock-dial 29, and to this end is provided with a central bushing 4l staked'to the gear 35 `and adapted to be rotatably mounted in the central aperture 28 of the clock-dial, the forwardly-projecting end of the bushing 4l having a concentric flange 42 overlying the adjacent edge of the central aperture 28 of the clockdial, to prevent the bushing from being withdrawn rearwardly therefrom. Immediately forwardly of the concentric flange 42 of the bearing-sleeve is an annular shoulder 43 of reduced diameter on which an alarm-set hand 44 is secured by a press t. In accordance with this construction, the alarm-set hand 44 is supported on the front of the dial in concentric relationship with the second hand 45, the minute hand 46, and the hour hand 41, which hands are supported, in turn, on the front of the clock-dial by the forwardly-projecting ends of the secondsarbor 2|, the minute-sleeve 21 and the hoursleeve 39 respectively, thereby providing a simple' and compact dial arrangement of pleasing appearance.

, The alarm-cam 34 of the longitudinally-slide.- ble hour gear-Wheel 3l.is adapted normally to be resiliently held in engagement .with the underside lof the alarm-setting gear 35 by the forwardly-biased leaf spring 36, the force of which acts against the underside of the hour gearwheel. In this normal position of the leaf spring, its alarm-latch 31 extends rearwardly through the clearance-aperture 38 of the front movement-plate to hold the alarm-armature of the alarm-mechanism in its normal inoperative position, as hereinafter described. For releasing the alarm-armature at a predetermined time, the alarm-setting gear 35 is provided with an aperture 48 in the path of movement of the alarm-cam 34 of the hour gear-wheel. Thus, as the latter rotates, its alarm-cam 34 will ultimately arrive opposite the aperture 48 in the alarm-setting wheel, whereupon the alarm-cam 34 enters therein, thereby releasing the hour gear-Wheel vfor movement forwardly on the minute-sleeve 21, which movement is effected by the force of the forwardly-biased leaf spring 36. The alarm-latch 31 is thus permitted to spring forwardly to release the alarm-mechanism as hereinafter described.

The alarm-setting gear 35 and the time-train of the clock are adapted to be rotated manually with respect to the dial by any conventional means (not shown) for setting the alarm-set hand 44 and the time-indicating hands 46 and 41 of the clock.

Referring to Fig. 3, the alarm-actuating means of the electric alarm clock comprises a pair of auxiliary pole-pieces of the motor stator, each auxiliary pole-piece comprising a single substantially Z-shaped strip of metal indicated at 49 and 50 respectively, formed of substantiallyflat metal stock and equivalent in thickness to the individual lamina of the stator, each auxiliary pole-piece being secured on the front faces of the respective poles of the stator, with the free ends of the auxiliary pole-pieces 49 and 50 extending inwardly in opposed spaced relationship over the field coil I6 of the stator. As shown in Fig. 3, the forward faces of the auxiliary pole-pieces lie in a common plane substantially parallel to and spaced immediately rearwardly of the end-closure plate I8 of the motor-casing.

The alarm-mechanism of the alarm clock comprises an alarm-armature indicated generally at 5I; and manually-operated means, indicated generally by the alarm-shutoff bar 52, for returning the alarm-armature from its operating position to its inoperative position, in which position it is held either by the alarm-latch 31 for automatic release or by the shutoff-bar 52 for manual release as hereinafter described.

The alarm-'armature 5l comprises an elongated arm 53 preferably of a resilient sheet metal, having an enlargement 54 at one end corresponding to its inner end, provided with an aperture through which projects the lower end of the alarm-armature mounting-means which, in the embodiment shown, comprises a supporting-post 55 secured at its opposite ends between the front and back movement-plates -of the clock-frame. The inner or enlarged end 54 of the armaturearm 53 is adapted to be secured to the adjacent end of the post for rotation therewith by meansa of a collar 56 to which the enlarged end of the alarm-armature is secured, the collar, in turn, being fixedly secured by a force fit on the corresponding end of the post 55.

The opposite or outer free end of the alarmarmature arm 53 is provided with a magneticplate or -shoe 51, which is secured thereto infa' plane substantially parallel to the plane of the armature-arm but spaced rearwardly thereof. In this connection, the back movement-plate I9 of the clock-frame is provided with a suitable aperture 58 for accommodating the magneticshoe 5l of the alarm-armature arm, the aperture in the back movement-plate being suitably shaped so as to provide for free oscillatory movement of the magnetic-shoe. As thus mounted in the frame of the timepiece, the magnetic-shoe 57 of the alarm-armature arm is disposed immediately adjacent the front face of the soundingplate I8 of the motor-casing. Hence, when the magnetic-shoe 51 of the alarm-armature arm 1s swung around into its normal operating position, itl will beV separated from the auxiliary polepieces 49 and 50 of the stator by the nonmagnetic sounding-plate I8 of tne casing, the spacing of the magnetic-shoeof the alarm-armature arm and the auxiliary pole-pieces being such that the magnetic-shoe will be vibrated by the auXili;

iary pole-pieces when the latter are energized As will be clear from the foregoing description and drawings, the direction of vibration of the magnetic-shoe 57 of the alarm-armature arm will be substantially perpendicular to the plane of rotation thereof and to the plane of the endclosure plate or sounding-plate i8, against which the magnetic-shoe 51 strikes to sound the alarm.

The forward end of the alarm-armature supporting-post 55 is provided with a dog 59 which is nxedly secured thereon immediately adjacent the rear face of the front movement-plate 2li and has outer and inner legs 55 and El respectively, the outer leg 65 of the dog being engaged by the reach 62 at the forward end of a coil r..

spring 63 which is mounted on the post 55. The reach 64 at the rear end of the coil spring is engaged with the aforesaid alarm-shutoff bar 52, which constitutes an abutment therefor. As so arranged, the forward reach of the coil spring acts normally, by engagement with the dog-leg 6D, to resiliently hold the alarm-armature in its operative position opposite the auxiliary polepieces of the field magnet and to resist pivotal displacement of the alarm-armature from its operative position to its inoperative position.

Thel displacement of the alarm-armature from its operative position to its inoperative position is effected positively by means of the aforesaid alarm-shutoff bar 52 which is slidably mounted r 'guide-aperture in the front movement-plate.

Thus, by moving the alarm-shutoff bar forwardly in its guide-slots of the clock-frame, its

cam-finger 55 will cammingly engage the outer leg 60 of the dog to positively rotate the latter in a clockwise direction, as indicated by broken lines in Fig. 1, thereby rotating the post 55 and simultaneously tightening up the coil spring 63.

Coincident with the rotation of the post 55, the alarm-armature arm secured thereon is posi- `tively swung into itsinoperative position, as indicated by broken lines in Fig. 1.

Suitable restraining-means are arranged to 6. engageI the alarm-shutoif'bar 52, tovhold itl in its aforesaid forward positionagainst the force of the tensioned coil spring 63, the force of which acts normally, through engagement of its respective reachesl with the aforesaid outer leg 8B of the dog and the shutoff-bar respectively, to rotate the dog in a counterclockwise direction and hence cam the alarm-shutoff bar rearwardly to its normal position. l

The aforesaid restraining-means comprises" a substantially L -shaped resilient catch 66 mounted on the back face of the back movement-plate and arranged to engage in a notch 6l in the corresponding edge ofthe alarm-shutoi bar, as illustrated clearly in Fig. 2. With the alarm-shutoff bar 52 held thus in its forward position by the aforesaid resilient catch, the inner leg 6| of the dog is positively held outwardly of the alarmlatch 3i' until such time as the shutoff-bar 52 is drawn rearwardly manually, to activate the alarm. On pulling the shutoff-bar 52 rearwardly positively to activate the alarm, the cam-finger of the shutoff-bar will move out of camming engagement with the outer leg of the dog, thereby releasing the latter to rotate in a counterclockwise direction under the urgency of the tensioned coil spring. Normally, an appreciable length of time will have elapsed between the time the alarm is shut off manually and the time the alarm is again activated manually, as. hereinabove. described, during which lapse of time the alarmcam will have ridden out of the clearance-aperture ofV the alarm-setting gear-wheel, thereby causing the alarm-latch 3'! to project into the path of movement of the leg 5! of the dog. Hence, the inner leg 6i of the dog will normally bring up against the alarm-latch 3l, whereby the dog and the alarm-armature arm secured to the dog-supporting post are held from rotating into operative position until such time as the alarmlatch is actuated by the alarm-setting gear tov release the dog. The latching surface of member 3l is constructed with a sloping surface on its terminal area, as shown in the view of member 3l, Figure 3, in dotted lines. The purpose of this sloping surface is to allow member 5i to pass by member 3 in the event that the shut off member 3i has been moved back to the latching position by the action of the clock train, all as hereinafter described.

For the purpose of describing the operation of the alarm-mechanism, let it be assumed that the alarm-armature 5I is held in its inoperative position, as indicated by the broken lines in Fig. l', by engagement of the dog-leg 6l with the alarmlatch Si and that the alarm-cam 34 of the hour gear-wheel 3i is engaged with the imperforate portion of the alarm-setting gear 35, which has been set by means of conventional manuallyoperated alarm-setting means, for releasing the alarm at a predetermined time, as indicated by the alarm-set hand 44 on the dial of the clock. As the hour gear-wheel 3l is rotated, its alarmcam 34 ultimately arrives opposite the aperture 45 in the alarm-setting gear 35, whereupon the force of the leaf spring 35, acting against the underside of the hour gear-wheel 3i, moves the latter forwardly on the minute-sleeve 2, thereby permitting the alarm-latch 37 to move forwardly out of the path of movement of the dogleg Bl of the alarm-armature arm to release the latter for swinging movement. Thereupon, the force of the tensioned coil spring 63 swingsthe alarm-armature 5l from its inoperative position around to its operative position, as shown in Fig.

1, wherein the magnetic-shoe 51 of the alarmarmature arm is immediately in front of the auxiliary pole-pieces of the stator of the motor, but separated therefrom by the nonmagnetic sounding-plate i8 of the motor-casing. In its operal tive position, the magnetic-shoe of the alarmarmature arm is vibrated by the energized auxiliarypole-pieces 49 and 50 of the motor-stator, the direction of vibration of the alarm-armature arm and its magnetic-shoe being substantially of the dog in a clockwise direction, as indicated by broken lines in Fig. 1, thereby rotating the supporting-post 55 and the alarm-armature arm 53 secured thereon in a clockwise direction to return the latter from its operating position to its inoperative position, the alarm-armature army being held positively in its inoperative position by engagement of the resilient catch in the notch of the forwardly-displaced alarm-shutoff bar. v

To reset the alarm-mechanism for subsequent automatic operation of the alarm, the alarm- :v

shuto bar is pulled rearwardly so as to disengage its cam-finger 65 from the outer leg -60 of the dog and permit the force of the tensioned coil spring to swing the alarm-armature arm back to its operative position. Normally, however, the fi. alarm-cam 34 of the hour gear-wheel will have moved out of the aperture 48 in the alarm-setting gear 35 so that the hour gear-wheel 3| will have been moved rearwardly on the minutesleeve, thereby pressing the leaf spring 35 rearwardly and projecting the alarm-latch 31 of the leaf. spring through the clearance-aperture 38 o f the front movement-plate for engagement with the inner leg 6I of the dog. Consequently, when released by the alarm-shutoff bar, the dog will promptly engage against the alarm-latch 3l and be positively held from counterclockwise movement until the alarm-cam 34 of the hour gearwheel has again dropped into the clearanceaperture of the alarm-setting wheel to effect automatic displacement of the alarm-latch.

The improved alarm-mechanism in combination with the superior mounting-means of the alarm-set hand, cooperate to provide an electric alarm clock of compact and dependable construction, relatively free from derangement and of neat and pleasing appearance, the compactness and simplicity of construction being characterized in particular by mounting the alarm-armature arm for movement to and from operative relationship with respect to the auxiliary polepieces of the motor-stator in a plane substantially perpendicular to the direction of vibration of the magnetic-shoe of the alarm-armature arm.

rlhe invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

1. In an electric alarm clock. the combination including: an electric motor embodying a bipolar field magnet and rotor; alarm actuating means comprising a pair of auxiliary pole pieces of said field magnet; an armature resilient in one direction; a rotatable mount for said armature having an axis parallel to said resilient direction; manual means for rotating said mount to remove said armature from the influence of said auxiliary poles; and means for returning said mount to a position bringing the armature into the influence of said poles.

2. In an electric alarm clock, the combination including: an electric motor embodying a bipolar field magnet and rotor; alarm actuating A; means comprising a pair of auxiliary pole pieces of said field magnet; an armature; a substantially flat spring mount for said armature; a rotatable mount for said spring, having an axis substantially perpendicular to the main plane of said spring; manual means for rotating said mount for removing said armature from the influence of said auxiliary poles, and spring means for returning said armature to a position under the influence of said auxiliary poles.

3. In an electric alarm clock, the combination including: an electric motor embodying a bipolar eld magnet and rotor; a clock train driven thereby, including a rotating cam; alarm actuating means comprising a pair of auxiliary pole pieces of said field magnet; an armature; a substantially flat spring mount for said armature; a rotatable mount for said spring, having an axis substantially prependicular to the main plane of said spring; manual means for rotating said mount for removing said armature from the inuence of said auxiliary poles; a latch controlled by said rotating cam for delaying the return motion of said rotatable mount; and spring means for returning said armature to a position under the iniluence of said auxiliary poles.

4. In an electric alarm clock, the combination including: an electric motor embodying a bipolar iield magnet and rotor; a non-magnetic casing for said motor; alarm actuating means comprising a pair of auxiliary pole pieces of said magnet mounted within said casing; an armature exterior to said casing; a substantially ilat spring for mounting said armature; a rotatable mount for said spring having an axis approximately perpendicular to the main plane of said spring; manual means for rotating said mount to remove said armature from the influence of said auxiliary poles; a clock train driven by said rotor; a cam driven by said train; latch means actuated by said cam for preventing the return of said mount to the inuence of said pole pieces; and spring means for returning said mount to a position under the influence of said pole pieces.

5. In an electric alarm clock, the combination including: a motor; a non-magnetic casing for said motor; a pair of supporting frames one of which supports said motor casing; a dial supported by the other of said frames; a gear train supported on or between said frames; seconds, minutes, and hours arbors attached to said gear train; a rotating cam gear driven by said gear train and supported by said hours arbor; a cam mating disk, an arbor for mounting said disk and frictionally mounted on said dial; an alarm indicating hand supported by said disk mounting arbor; a spring latch mounted on one of said frames for impelling said cam gear against said cam mating disk; a pair of auxiliary pole pieces of said iield magnet within said casing; an armature exterior to said casing but in a position to be influenced by said auxiliary pole pieces, and lying in a plane parallel to said frames; a flat spring for mounting said armature; a shaft supported by s'aid frames for mounting said flat spring; a double ended arm attached to said shaft and having one end contiguous to said latch; a shutoi blade mounted slideably in said frames and adjacent to the other end of said double ended arm, whereby in-and-out motion of said arm tends to rotate said shaft and thus remove said armature from the influence of said iield in a direction at right angles to its direction of vibration; and a spring on said shaft tending to oppose the motion of the same imparted to it by said blade.

ARTHUR B. POOLE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

